If a newspaper writer has a 1 sentence plagiarism from a book is he guilty of copyright infringement ?
Probably not, but the details matter. The court would ask why he took the sentence (was it for news coverage? commentary? no good reason?) and how harmful that was to the original author (was that the only sentence that mattered in the book?). Usually something so small, in the newspaper, will be justified and hence excused under copyright law's "fair use" doctrine.
Hope that helps. Good luck.
Professor of Law at Top-Tier Law School, specializing in patent & copyright
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